How to give POA to my wife for the property in India?

My husband has some ancestral property in India. He does not travel to India as often as I do because his parents are not alive. However, I go every year. So, he would like to give a POA to me (both of us are NRI’s). What is the process? I have given my POA to my Dad who is in India. But in this case both of us are in abroad. Please explain.